Method for applying sheets to printing cylinders



June 12, i923; Mssg?? W. GAMBLE ET AL 1 METHOD FORr APPLYING SHEETS TO'PRINTING CYLINDERS Filed Sept. 8, 1922 2 Sheets-Sheet l Pie fm2/Vir Jun@ l2, 12923. 3,458,477

W. GAMBLE ET AL METHODA FOR APPLYING SHEETS TO PRINTING yCYLINDERS Filed sem. ,8. 1922 2 shets-sheet 2 El Ff 25, IHHEM l l Pea, mii/@ A omar Com -`STATES PATENT OFFICE.

wrm. GAMBLE AND MALCOLM owEN, 4or LONDON, rNeLAiNn, SAID GAMBLE.

' Assioma ro a. w. rnNnosE AND COMPANY LIMITED, or LONDON, mic .a if .1

' ,METEOD FOR APPLYING SHEETS 'i730 PRINTING CYLINDEBS.

Application med September 8, 1929. Serial No. 587,014.

l metal on cylinders for intaglio and photogravure printing.

The main object is to obtain a firm and even surface on the sheet after wrapping has been edected, so that the best printing results are obtainable and especially so that sheets may be removed andreplacedron cylinders so that 'they can be kept iorrurther work if desired. t

ln the accompanying -drawings are illus- -tinted preferred constructions embodying the present invention: v Fig. 1 is a side elevation Oi the tension apperatus;

Fig. 2 is a plan of the tension apparatus;

Fig. 3 is an end view of a' printing cylinder constructed according' to the present invention showin the method of providing pegs *for lattachingn the sheet, and theinitial position oi the sheet for a wrapping operation' Fig. l is a similar view to Fig. '3 showing the position of the parte at the nal movement of 'the wrapping operation and at the beoinning ci the nal clamping ci the sheet;

l ig. 5 is a detail view showing the presser members, hereinaiterireierred to, associated with a dove-tailed base portion of the capniet Piece; W

ig. 6 is a similar view to li lgs. 3 and 4: showing he wrapping and hiring operations le'te Fig. 7 is a pictorial view or an etched sheet constructed according to the present invention. v

Reterring hrst to Figs., 1 and 2 of the drawin s, the numerals 1 and 2 indicate @Sie longitu inal and transverse members ci a framework, at one end of which is disposed `on. the longitudinale, bearings 3 for the reception of a s indle 4: adapted to carry fa printing cylin er, indicated by the `nunieral 5. The bearings are open at the top so that the spindle may be immediately removed, if

` around. the cy re uired byliiting it from the hearings. th spindle at one end, outside a bearmg 3, is fixed a worm wheel 6, and litted on the adj acent longitudinal is a worm 7, ada ted to be operated by any means, such, or instance, as the handle 8.

. At the other end of the framework, bearings 9 are arranged on the longitudinalsin the same manner as the bearings 3, the bear- 1ngs9 also being preferably open lor the direct reception of a spindle 10, on which is mounted 'a sprocket wheel 11 arranged centrally of the frame. At one end of the s indie l0 is mounted a brake drum 12, e out which is litted a-friction device 13, which may be adjustable about the drum by means ofthe device 14, the segments of the braking device being pivote ly connected, as indicated at 15, to an adjacent portion of e longitudinal member 1. The rotation oi the member le causes the segments of the device 13 to move about their pivots in order to. vary the 'rictionc'l engagement with the drum 12. Fixed near the periphery ci the sprocket wheel 11 is a chain 1% which is adapted to wrap round the sprocket wheel, and which carries at its free end e clamping element 17 for attachment oi a sheet 18 intended to be wound around the printing cylinder 5. ln order to maintain the clamping bar parallel with the axis 10, the clamping bar is connected'to the chain 16 by means ot a block 19 carrying a toothed wheel 2U, over which passes a second chain or other denible member 21, connected to both ends ont 'the clamping bar.

ln use, one end oi the sheet 18 is htted to the usual gap 22 formed in the printing cylinder, and the other end is attached to the clampin bar 17. The sprocket wheel is then rotate to coil the chain around it until the sheet 18 is pulled ont and strained under tension. The loralrinlg'device is then applied'nntil it revents'any reverse rota'- tion of the spind e 10 which would sleclen the tension in the sheetic, @ne to the position oi the bearings one to another on the platform, the sheet, when so strained, is disposed tangentinlly to the periphery the cylinder 5 then to wrap the lsheet l linder 5, the wormv 7 is rotated, and by gearin with the worm Wheel 6, causes the cylin er ,5 mounted on 'the spindle d to be rotated away from the tensio device and to wrap the sheet 18- Sti ice

lll

around it," while'the tension applied to the sheet is maintained.

It may here be pointed out that the worm 7 prevents a. reverseJ` rotation of the cylinder which the tension of the sheet tends to effect. The' sheet having been wrapped entirely-round the vcylinder until its end attached to the clamping bar 17 overlaps the gap 22 in the cylinder, that end of the sheet is then xed within the gapA and the clamping bar released from-the sheet, when an extra material may be removed.

. ther applicationsy of this part of the invention will be apparent to those engaged in the printing art. For instance, the method may be used to wrap cylinders with the rubber sheets by which oil-set printing is accomplished, and it may also becially adapted for the reception of the end of a. sheet before tension is applied and for xing the sheet when -it is wrapped around the cylinder, and further, provide a sheet especially adapted to be subjected to tension, we construct the cylinder, its parts,

incdrawings.

and the sheet as now to be described with reference to Figs. 3 to 7 of the accompanytThe slot or gap 22 of the cylinder is provided with a steel reinforced jaw 23, the jaw carrying pegs 2i for attachment oi.a the etched sheet 18. The sheet is anchored to the pegs 2d and-tension is applied as already described, the cylinder'being rotated until the other end of .the sheet overlies .the

gap 22.

owever, to prevent detachment of the sheet from the egs 2d during rotation of the cylinder, a istance piece 25 is inserted in the slot 22 and on theA jaw 23. rllhen in order to prevent the distance' piece 25 moving, latches 26 are arranged at each end of the cylinder which engage over lugs 27 of' the distance piece, as will. be readily. understood. (These latches are omitted from Fig. i for sake of clearness.) rllhe sheet having been wrapped around the cyl-4 inder to the position shown in Fig. 4 a base portion 28 of a capping piece is placed over .the sheet associated with a sectional presser member indicated by the reference numeral 29. he presser member 29 and the base portion 28 are then thrust into the slotbyrotating bolts B0 which extend through thesections of the presser member, the base portion 28 ofthe capping piece, the1 sheet 18, the distance piece 25,l and thejaw 23 within the islot, thereby firmly clamping the free end of the sheet against thev distance piece. In this final position the dove-tailed base portion 28 is tightl engaging the distance piece 25, holdingl t e free end of the sheet sandwiched therebetween. The final position lhaving been vreached the sections of the presser .i

member 29 are removed one by one, and the bolts 30 are replaced by shorter bolts 3l having-their heads countersunk on the base portion-28 of the capping piece.4 Then in order to cover the heads and to fill the slot of the cylinder an undercut top portion of the capping piece, indicated by the numeral 32 is slid over the base portion 28, as will be clearly understood by reference to Fig. 6.

In such construction the distance piece and capping piece willY preferably 'be soidimensioned that the outer face of theV capping piece lies substantially in the peripheral circle of the cylinder; it may, however, be

.a little higher, or a little lower, without causing trouble.

In order that the printing sheet 18 may withstand the tension applied for the wrapping operation and also be suitable for the" final clamping operation referred to, it-is provided at each end with perforations as shown in Fig. 7, and one or both ends are reinforced, for instance, by rolling them over a rod 33. The loopsso formed may be made a rrture in any suitable manner, for instance, by soldering or rivetting, but it is not essential that such a nture should loe made.'

ln operation, the rod 3%v will lie immediately below the pegs 2e, and further will take and distribute the edort on the sheets and tearing will be avoided. The other end of the sheet may be similarly formed so that the clamping member l? has a goed` gripping surface, lont in any case the row of perorations 3d will be included as they are necessary for the passage of the bolts 30 or 3l. i

The linal clamping operation having been edected, the free end ol the sheet 18 is scored along the edge of the capping piece and fractured by' bending it to and fro, and it will be noted that the end of the sheet so fixed will have been passed down one side of the capping piece within the 'slot sand wiched between the capping piece and the distance piece, and will extend upwardly between the otherside of the capping piece and the slot. l

The construction just described is ap liceble when the slot on the printing cy inder oblique to the axis, as shownn Fig. 2 of j Y f dit peripheryjof the cylinder, thereby ineens? the drawin. en the slot is oblique the an'le is suo that the doctor is alvva s pro vi ed with a suprting surface vvhi e passing over a joint tween the copper surface and the capping` piece.

The rake of the slot in the printing cylinder is preferably not less than one yinch in ninety-six inches.

llt should be lparticularly noted that by the manner oi xing the printing sheet come1 prised in the present invention, only a narrow slit in the cylinder is necessary.

By the use oi an oblique slot any clic :lgnoise whilst periormin the Wiper is substantially eliminated.

acter and to the fact that the doctor is car ried by the second halt of the rake betere leaving the rst, thus obtaining a clean wipe at every impressioni.,

When an oblique slot is formed in the sirius ecient support to the doctor as 1t passes over a joint, the doctor need not he suported h a capping piece having its outer ace leve with the periphery of the cylinder, as the rising of the doctor from a lower level would be gradual. Further also, the usual mechanism for reciprocating the doctor and for pressing the doctor on to the cylinder ma be retained.

edective means for securing a sheet on a printing roller, and improve the roller and the sheet, whether the sheet is to be made vof copper, zinc, rubber, Celluloid, hardened .imprinting ,surface todprintingl cylinders,

urther,'the doctoris maintained at a constant pressure while ypassing over a joint due to its narrow charl i1 our invention lArve provide a simple and' wherein one end of the sheet is attached on one side of the gap of the cylinder and the sheet is stressed mechanically under tension tangentially to the cylindrical surface, the

linder being held against rotation during t e initial straining and then while the strain is maintained, rotated to wrap the sheet ti htly around it, Whereon the other endoi the sheet is fixed within the gap aforo sai 2. A method oi applying sheets tor use as a printing surface to printingcylinders, wherein one end ci' the sheet is attached on one side of the gap of the cylinder and the' sheet is stressed mechanically under tension tangentially to the cylindrical surface, the cylinder being held against rotation during t e initial strainin and then while the strain is maintains rotated to Wrap the sheet -tihtly around it, Whereon the other end of t e sheet is pressed into the ap while the tension red.

3. A method of applying sheets for use as a printingl surface to rinting cylinders, wherein one end of the s eet is attached on one, side of the gap of the cylinder and the sheet is stressed mechanically under tension tangentially to the cylindrical surface, the cylinder being held against rotation during t e initial strainin and then while the strain is maintains .rotated to wrap the sheet tightly aroundI it, whereon the other is maintained vand tereafter end of the sheet is pressed into the ap, the

end being then fixed in sections wh e pressure is. retained on the end andthe tension vmaintained.

In testimony whereof we ax our signatures. 

